There currently exists a number of lighting fixtures utilizing LEDs as the light source. While such fixtures provide some beneficial features, they nevertheless suffer from a number of limitations, including but not limited to, uneven light distribution and brightness, high material and component costs, difficult and time-consuming assembly, and cumbersome housing configurations that hamper installation and thus prevent custom applications. An example of a lighting fixture suffering from the above limitations is disclosed in U.S. Pat. No. 6,283,612. There, the fixture comprises a hollow tube 20 with a single, linear array of LEDs 44 extending from a printed circuit board 22, along with a plurality of resistors 38. The bottom 26 of the board 22 has a full length conductive bus 28 and a full length conductive negative bus 30, with each bus 28, 30 located adjacent an opposed outside edge of the board 22. The anode 46 of the LED 44 is in communication with a second lead 42 of one of the resistors 38, and the cathode 48 is in communication with an adjacent LED 44 connected in series. A pair of end caps 50 are hermetically sealed to the tube 20 with adhesive 54 to secure the circuit board 22 within the tube 20, where the end caps 50 have a bore 56 that accept a cord 60. A resilient gasket 58 is disposed between the circuit board 22 and each end cap 50 to further secure the circuit board 22 within the hollow tube 20. An external power supply 64 provides direct current power to the single array of LEDs 44. A U-shaped mounting bracket 66 is utilized to mount the tube 20 for installation. Because the LEDs 44 are linearly arranged in a single plane, the tube 20 produces a limited range of light that is uneven and susceptible to undesirable “hot spots.” This poor lighting performance renders the tube 20 commercially unfeasible.
Further, refrigerated display cases, often referred to as coolers or freezers, are commonly found in grocery stores, markets, convenience stores, liquor stores and other retail businesses for the preservation and display of food and beverages. Conventional display cases comprise an inner refrigerated space defined by a collection of structural elements, and an opening further defined by the structural elements that is accessible by a sliding or swinging door. Typically, the door is formed from a plurality of frame members that support at least one layer of glass and a handle. The collection of structural elements that form the display case include interior and exterior frame members, including “mullions” which are vertical elements that extend between upper and lower frame members. An end mullion is a peripheral vertical element that is located at one end of the display case, and a center mullion is a central vertical element that is located between two openable doors. The mullion provides an engaging surface for the door seals that are used to maintain the lower temperature within the display case. As such, the mullion is part of a door frame sealing system for the free-standing display case.
Certain retail businesses, such as convenience and liquor stores, include a “walk-in” cooler or room instead of a free-standing refrigerated display case. These walk-in coolers are not free-standing as recognized within the industry, however, they include a number of similar components including mullions and openable doors with seals.
Regardless of whether the refrigerated case is free-standing or walk-in, the door frame members and the door glass conduct ambient heat into the display case and function as a condensation surface for water vapor present in the ambient air.
The present invention seeks to overcome certain of these limitations and other drawbacks of the prior art, and to provide new features not heretofore available. A full discussion of the features and advantages of the present invention is deferred to the following detailed description, which proceeds with reference to the accompanying drawings.